The Interactive Diet and Activity Tracking in AARP (IDATA) Study and the Multi-cohort Eating and Activity Study for Understanding Reporting Error (MEASURE) are related initiatives conducted to assess the measurement error properties of diet and physical activity assessment instruments against biomarkers and other reference measures. MEASURE includes three studies: the IDATA Study and the Men?s and Women?s Lifestyle Validation Studies conducted by Harvard University. Data elements common to the three studies include self-report instruments used to assess physical activity behavior, including a 24-hour recall of time use, recall questionnaires, and monitor wear logs. All of these data elements contain free text responses provided by study participants that require standardization and recoding in analytic data files with application of metabolic equivalent (MET) values to facilitate energy expenditure estimate. The purpose of this procurement is to code the verbatim physical activity and time use reports from monitor wear logs, recall questionnaires, and 24-hour recalls into variables with standardized values that may be linked to MET values tabulated in the Compendium of Physical Activities by Ainsworth and colleagues (https://sites.google.com/site/compendiumofphysicalactivities/).